This invention relates generally to devices and methods for cleaning information disks, particularly such as so-called compact laser disks of the type used to store information in audio, video, and/or computer memory applications and the like. More specifically, this invention relates to an improved cleaner unit for removing particulate and oil-based substances from the surface of an information disk in a non-contact manner.
Laser type information disks are relatively well-known for use in storing selected information which can be optically retrieved through the use of a relatively low power laser. Such disks typically comprise a thin metallic film or the like sandwiched between overlying disk-shaped layers of a substantially transparent plastic material. Selected information for use in audio and/or video or computer memory applications is transferred to the metallic film through the use of a modulated laser beam which etches or pits the film. The surface of the film is thus disrupted and constitutes a physical representation of the stored information, wherein this information is typically arranged in a closely spaced array of concentric tracks. A readout laser responds to the resultant reflective and nonreflective geometry of the film to provide electronic signals capable of demodulation to retrieve the stored information. The use of compact disks of this general type has recently gained widespread popularity for use in modern audio and/or video systems, as well as for use in storing information in modern computer systems.
Compact laser disks of the above-described type beneficially provide a space efficient and relatively durable information record. However, dirt and other foreign materials such as dust and oil-based spots attributable to fingerprints and the like can interfere with accurate information retrieval. It is therefore necessary, in some instances, to clean the plastic outer surface of the compact disk for purposes of improving readout resolution.
In the past, a variety of disk cleaner devices and related cleaner methods have been proposed for use in removing dirt and other foreign matter from the surface of an information storage disk. Such cleaning devices have generally involved contact cleaning methods using soft pads or brushes or other physical structures which directly contact the disk surface, typically in conjunction with a selected cleaning solvent. Examples of such contact type cleaning devices are typified in U.S. Pat. Nos. 4,202,071; 4,520,470; 4,654,917; and 4,662,025. Unfortunately, the use of cleaner pads and other direct contact implements can scratch or mar the disk surface, resulting in permanent disk damage which can interfere with information readout.
Noncontact cleaner devices have been proposed for use in removing dirt from the surface of a conventional grooved phonograph record. See, for example, U.S. Pat. No. 3,747,942. In this device, a cleaning solution is sprayed over the surface of a rotated record for purposes of washing unwanted debris therefrom. However, this device requires significant manual manipulation of components to properly install a phonograph record to be cleaned and to apply cleaning solution to the surface thereof. Moreover, the device does not provide adequate cleaning solution control to prevent cleaning solution from splashing onto or otherwise contacting other equipment components. Still further, subsequent to a cleaning step, it is usually necessary to dry the cleaned record, wherein such drying step is normally accomplished with a soft cloth or the like in direct physical contact with the information surface of the record.
There exists, therefore, a significant need for an improved cleaner unit adapted for noncontact cleaning of an information disk, particularly wherein the cleaner unit is designed for closely regulating flow of a selected cleaning solution, and further wherein the cleaner unit includes means for drying a cleaned disk in a noncontact manner. The present invention fulfills these needs and provides further related advantages.